When we go back in history, we saw that the first animal with the characterizes of the man descended of 4.000.000 years ago, the Australopithecus amanuenses. We can't imagine how those ape's look like.. The first artwork ever found is the "Venus of Tan Tan" This Venus stems of Morocco, ad has an age from about 500.000-300.000 years b. Chr. There is a big discussion in the -art, -biological, science-world, without any results of course. This "tan tan" is just an accidental object, created by the geological process of mother nature. The other side is just that it is made by human hands..... the real question is of there was art before 100.000 years b. Chr.
The first general art objects date from the late Paleolithic. The first real cuneiform was made in 350 0 B.Chr. So what we see is that the human who began to think (in a practical way), was about 150.000 years old. The The first human beings with brains that look like our brains were homo sapiens. The first of this sort was a woman, born in Africa.
So when we look to the first cave-paintings, like Lascaux, then in fact it is not more than communicate. (maybe to tell a story)
A image says more than 1000 words. In the sixth century there was made the first oil painting in a cave in Kabul. This is the first with colours, the image look likes a buddha. In 1400 A.chr. there were more colors and the (religious) artists made craft for cathedrals and other "old" churches. That were the first fresco's.
After the fresco paintings, there became more paintings with a various color palette and more emotion and esthetic value. The old painting masters, have learned it from other's and especially to do it a lot. In the old academies there are some secrets about compositions, perspectives, color contrasts, figure/landscape drawing, canvasses, paint making.
So here some details of 3 works you saw in the portfolio, with note that you see the plasticity, color and writing, when you look closely.